This invention relates to a novel crystalline structure of n-octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate (hereinafter referred to as compound (I)) as an industrially useful antioxidant.
The aforesaid compound (I) already available on the market is white fine powders with low bulk density, which is easily diffused into air during various handlings and not satisfactory in transportability, workability and measurability thereof.
The present inventors have found that the aforesaid problems can be solved by the flake-like compound (I) with good quality, which was obtained by melt granulation and melt solidification.
Based on further research works, the inventors have found that the selected conditions of the melt solidification gave the compound (I) a novel crystalline structure quite different from the crystalline structures of prior commercial products. These findings resulted in the accomplishment of this invention.